Publication Abstract

Demersal fish populations in the coastal waters of the UK and continental N.W. Europe from beam trawl survey data collected from 1990 to 1995

Demersal fish populations in the coastal waters of the UK and continental N.W. Europe from beam trawl survey data collected from 1990 to 1995

S.I. Rogers, A.D. Rijnsdorp, U. Damm and W. Vanhee

Samples of the demersal fish fauna have been collected by beam trawl from the coastal waters of North-west Europe (49°-57°N, 8°W-9°E) by the UK, The Netherlands, Germany and Belgium, since 1990, during the third quarter ofthe year. These data have now been combined and the mean catch rates offish have been used to describe the community structure of fishpopulations throughout the region. Samples were collected using beam trawls of commercial design and fitted with fine mesh liners, and data collected included catch numbers of all species taken (number of fish/hr/8m beam trawl), measurements of juveniles and adults, and ages ofcommercially important species. Environmental data at each station position, including the surface water temperature and salinity, were also collected. The species composition of the demersal fish fauna was generally richer in the Channel and west of the British Isles than in the North Sea, although only 8 out of atotal 19 flatfish species were found in abundance in this westerly region. Changes in community structure within small spatial scales were subtle as species compositions formed part of a continuum over the entire continental shelf. Consistent patterns offish population structure were generated on the North Sea Continental coast by the abundance of dab Limanda limanda. In the Channel and to the west ofthe UK the demersal assemblages were more species rich than the North Sea and, although dab was still an important member ofthe underlying fish assemblage, the abundance of other species, especially poor cod Trisopterus minutus, solenette Buglossidium luteum, plaice Pleuronectes platessa, and the lesser weever, Echiichthys vipera, allowed a range of different groups to be identified. The dominance of different species indifferent size classes was a key feature of the community structure, and contributed to their classification into specific types ofhabitat. Flatfish were the largest group by weight in the smaller length classes (<30 cm), and in western areas the elasmobranchs dominated the larger size classes. The distribution by region and by depth, the mean catch rates and indices of absolute abundance of flatfish species caught during the survey were described, and partly explained by the environmental limitations imposed on some early life history stages.

Reference:

S.I. Rogers, A.D. Rijnsdorp, U. Damm and W. Vanhee, 1998. Demersal fish populations in the coastal waters of the UK and continental N.W. Europe from beam trawl survey data collected from 1990 to 1995.Journal of Sea Research, 37: 79-102

S.I. Rogers*, A.D. Rijnsdorp, U. Damm and W. Vanhee

Journal of Sea Research, 37: 79-102